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Towel Hamstring Curl
Why Include This
This is a home-friendly way to load the hamstrings eccentrically — the same training stimulus behind eccentric knee-flexor programs. Eccentric hamstring strengthening (best studied as the Nordic hamstring exercise) has strong RCT and meta-analytic support for reducing hamstring strain injury incidence in athletes and for building fascicle length and eccentric strength, both linked to injury risk. The towel/slider curl is a lower-load, easily scalable regression of that principle: it lets a patient train the hip-hinge-into-knee-flexion eccentric pattern early in rehab or before they can tolerate a full Nordic, using only a towel and floor. It is a good indication for hamstring strain rehab, posterior-chain endurance, and as a bridge toward Nordic curls. Honest caveat: the specific towel/slider variant has limited direct trial evidence — its support is extrapolated from the well-studied eccentric hamstring literature and from EMG showing high hamstring activation in slider/bridge curls — so I have set the evidence level to moderate rather than strong.
Evidence basis: moderate
Positions & Range of Motion
- Start
- supine, knees bent, heels on a folded towel on a smooth floor, arms at sides
- End
- hips lifted into a bridge (knees-hips-shoulders straight line) with heels slid out until legs are nearly straight, then dragged back in by curling the knees, hips held level throughout
- Range of Motion
- eccentric-to-concentric knee flexion/extension from ~90° bent to near-full extension and back, hips maintained in bridge
How to Perform
Lie face-up with knees bent and heels resting on a folded towel on a smooth floor. Lift into a bridge, then slowly slide the heels away from you until the legs are nearly straight (letting the hamstrings lengthen under load), and drag the towel back in by curling the knees to return. The towel on a slick surface creates the low-friction glide that turns a floor bridge into a sliding knee-flexor curl.
Opens a YouTube search for “Towel Hamstring Curl”
Coaching Cues
- 1
Keep your hips lifted the whole time — the tabletop line from knees to shoulders should not sag as your feet slide away.
(verbal) - 2
Slide out slowly, taking 3 to 5 seconds; the effort is in resisting the stretch, not in flinging the heels out.
(verbal) - 3
Drive your heels down into the towel to drag it back in, feeling the back of your thighs do the pulling.
(verbal) - 4
Stop the slide-out at the point where your hips start to drop or you feel it in your low back, and build range from there.
(verbal)
Evidence-Based Dosing & EMG Data
2-3 sets of 6-10 controlled reps, emphasizing a slow 3-5 second eccentric slide-out, 2-3 times per week on non-consecutive days. Progress by adding range, reps, or moving to single-leg once form and hip height are maintained without low-back strain.
Muscles Involved (9)
Primary Movers
Secondary Movers
Stabilizers
Lengthened / Stretched
Synergists & Assistors
Easier Variations ↓
Partial-range double-leg curl
Slide the heels out only part way and stay in a range where the hips stay fully lifted, gradually extending the distance as strength improves.
Bridge with assisted return
Use both legs and lightly push through the arms/heels to help drag the towel back in, reducing the concentric demand on the hamstrings.
Harder Variations ↑
Single-leg towel curl
Perform the slide-out and curl-in on one leg with the other foot lifted, roughly doubling the eccentric load on the working hamstring.
Tempo eccentric emphasis / Nordic progression
Slow the slide-out to 5+ seconds for maximal eccentric loading, then progress toward the Nordic hamstring curl for full high-load eccentric training.
Target Movements (2)
Why This Exercise Matters
Everyday activities this exercise helps you do — essential means it directly trains the capacity the task needs:
Goals This Helps With
Rehab, performance, prevention, and mobility goals this exercise supports — essential means it's a cornerstone:
Research Notes
claude-researched 2026-07 (home/bodyweight), panel-verified muscle roles + rationale. Sources not yet linked.